Reviewed August 2026

Islam and Christianity: what's shared, what's not

The two largest faiths on earth share Abraham, profess one creator God, and hold prophets, prayer, and a Day of Judgment. And their cited institutions disagree, on the record, about who Jesus is, the Trinity, the crucifixion, Muhammad, and the Qur'an. Here each tradition is described from its own institutions' documents (the Catechism and church catechisms for Christianity, Dar al-Ifta and Yaqeen for Islam), with the disagreements stated in both directions and no winner declared.

The comparison, side by side

For Islam, the sources are Dar al-Ifta, Yaqeen, and ICNA; for Christianity, the Catholic Catechism, the Orthodox Church in America, and named Protestant bodies. Both lists stay wide because "Christianity" is Catholic, Orthodox, and hundreds of Protestant traditions, not one creed, just as Islam is Sunni and Shia with schools of its own.

Start with the shared floor: one God, Abraham, and Jesus revered

Harvard's Pluralism Project states that Abraham is 'acknowledged as the father of the lineage of faith by the Jewish, Christian, and Islamic traditions.' Both faiths profess one creator God, and both hold prophets, revealed scripture, prayer, a Day of Judgment, heaven, and hell. The overlap runs deeper than many expect: the Vatican's own Nostra Aetate says of Muslims, 'Though they do not acknowledge Jesus as God, they revere Him as a prophet.' That's the shared floor; the walls differ. Whether the shared profession means the same God is itself a debated question this page's companion guide maps position by position.

Who Jesus is, and the Trinity

Islam

Egypt's Dar al-Ifta: Jesus 'is a Messenger of God and NOT divine or son of God'; and, per Yaqeen Institute, 'Muslims do not believe that Jesus was crucified or killed.' Islam's strict oneness (tawhid) rejects the Trinitarian formulation entirely.

Christianity

The Catholic Catechism: Jesus 'is the eternal Son of God made man,' crucified and risen. The Catechism confesses 'one God in three persons,' which is why 'Christians worship three gods' misstates Christianity's own claim.

This is the real, unresolvable-by-a-website center of the difference.

Scripture and prophecy: where each says the other stops short

Islam

In Dar al-Ifta's position, Islam accepts that the Torah and Gospel originated as divine revelations while maintaining the Qur'an's final authority and the obligation to follow Muhammad as the final prophet.

Christianity

The Orthodox Church in America's catechetical text states plainly that 'Christians reject Islam's claim that Muhammad was a true prophet' and that the Church does not accept the Qur'an as the Word of God; the prophets' witness, in Christian teaching, culminates in Christ.

The claims are not mirror images, so they appear here exactly. Both belong on the page; neither gets a verdict.

Sin and salvation: closer than the slogan, still different

Islam

Humans are 'born free of sin' (ICNA), with no original sin; yet Dar al-Ifta says entry to heaven is 'first and foremost, by God's grace not by our deeds.'

Christianity

Catholicism teaches original sin (though it 'does not have the character of a personal fault' in Adam's descendants) and that 'Justification has been merited for us by the Passion of Christ,' while also teaching that faith without works is dead.

The slogan says 'Christianity is faith, Islam is works'; both traditions' own sources complicate it. Grace matters in both; the mechanism (Christ's atonement versus direct divine mercy with repentance) is where they genuinely part.

Worship, clergy, and internal variety

Islam

Five daily prayers with Friday congregational prayer. Islam has 'no intermediaries between the worshiper and God' (Dar al-Ifta) and no sacramental priesthood, though imams, scholars, and, in Shia Islam, the marja exercise real teaching authority; Sunni and Shia schools rule differently on real questions.

Christianity

Catholic life centers on Sunday Eucharist, and Christian liturgy varies enormously by church. Catholicism ordains bishops, priests, and deacons, while Southern Baptist churches are each 'independent and self-governing.' Catholic, Orthodox, and Protestant Bibles don't even share one canon.

Neither faith is a monolith.

How many, as of 2020, and the standing invitation to talk

Pew's estimates for 2020 (published June 2025): 2.3 billion Christians (the largest group) and 2.0 billion Muslims (the fastest-growing over 2010-20, driven chiefly by demographics, not conversion); Pew's switching data shows people entering and leaving Islam in roughly offsetting numbers. And on speaking across the line, the institutions themselves lean in: 'A Common Word,' the collective letter from Muslim scholars to Christian leaders, declares 'The future of the world depends on peace between Muslims and Christians,' and the US Catholic bishops' dialogue committee writes, 'As disciples of Jesus we have to make every effort to triumph over fear.'

Islam-and-Christianity questions, answered plainly

What do Islam and Christianity have in common?

Both are Abrahamic monotheisms, Harvard's Pluralism Project notes Abraham is acknowledged as the father of the lineage of faith by Jewish, Christian, and Islamic traditions, professing one creator God, with prophets including Abraham and Moses, revealed scripture, prayer, charity, a Day of Judgment, and heaven and hell. Jesus is revered in both: as God's eternal Son in Christianity, and as a prophet and messenger of God in Islam, the Vatican's Nostra Aetate itself records that Muslims 'revere Him as a prophet.'

What is the main difference between Islam and Christianity?

Who Jesus is. The Catholic Catechism calls him 'the eternal Son of God made man,' crucified and risen; Dar al-Ifta teaches he is a messenger of God and not divine, and Yaqeen Institute states that Muslims do not believe Jesus was crucified or killed. The Trinity divides the same way: Christianity confesses one God in three persons; Islam's strict oneness rejects that. Salvation follows from it, Christ's atonement in Christianity versus God's direct grace with faith and repentance in Islam.

Do Muslims believe in Jesus?

Yes, centrally, Islamic institutions revere Jesus as a messenger of God, and the Vatican's Nostra Aetate itself records that Muslims 'revere Him as a prophet.' What Islam denies is his divinity and sonship, Dar al-Ifta: 'a Messenger of God and NOT divine or son of God', and Yaqeen Institute states that 'Muslims do not believe that Jesus was crucified or killed.' 'Muslims don't believe in Jesus' and 'Muslims believe the same things about Jesus' are both wrong.

Do Christians and Muslims believe in the same God?

The traditions themselves answer differently, so attribute the answer: Vatican II states Muslims 'adore the one God,' while some evangelical theologians argue the conceptions are irreconcilable because of the incarnation. Both agree the theological descriptions differ, on the Trinity above all. Our same-God guide maps the full range of positions by name.

Which is bigger, Islam or Christianity?

Christianity, per Pew's estimates for 2020 (published June 2025): about 2.3 billion Christians to 2.0 billion Muslims. Islam grew faster over 2010-2020-21% versus 6%, driven mainly by younger age structure and birth rates, not conversion. Claims that Islam 'will overtake Christianity by 2050' come from older projections; Pew's current data runs only through 2020.

Can a Christian visit a mosque, or a non-Christian visit a church?

Yes, both directions, in writing, with policies varying by congregation. San Antonio's Northside Islamic Center says it 'is open to non-Muslims of all faiths and backgrounds' and invites observation of prayer; the Church of England's visitor guidance says 'All are welcome at church' and, on participation, 'Join in with as much or as little as you like.' One Catholic etiquette note: the USCCB welcomes non-Christians at Mass but states 'we cannot admit them to Holy Communion', and its guidelines encourage all who are not receiving Communion to pray during that time.

Each tradition's claims are quoted from its own institutions. Where they contradict each other (the Trinity, the crucifixion, Muhammad's prophethood, the Qur'an's status), the contradiction is presented, not adjudicated. Qadir is a directory run for the Muslim community and open about that; it declares no winner between the truth claims of the world's two largest faiths.

The famous question, do the faiths worship the same God? →See for yourself, visiting a mosqueInterfaith events and open houses by city